2. Write the number as an improper fraction.
- 511.5 can be written as an improper fraction.
- An improper fraction = the numerator is larger than or equal to the denominator..
Write down the number divided by 1, as a fraction:
511.5 = 511.5/1
Turn the top number into a whole number.
- Multiply both the top and the bottom by the same number.
- This number is: 10.
- 1 followed by as many 0-s as the number of digits after the decimal point.
511.5/1 =
(511.5 × 10)/(1 × 10) =
5,115/10
3. Reduce (simplify) the fraction above:
5,115/10
to the lowest terms, to its simplest equivalent form, irreducible.
To reduce a fraction to the lowest terms divide the numerator and denominator by their greatest (highest) common factor (divisor), GCF.
Factor the numerator and denominator (prime factorization).
5,115 = 3 × 5 × 11 × 31
10 = 2 × 5
Calculate the greatest (highest) common factor (divisor), GCF.
Multiply all the common prime factors by the lowest exponents.
GCF (3 × 5 × 11 × 31; 2 × 5) = 5
Divide both the numerator and the denominator by their GCF.
5,115/10 =
(3 × 5 × 11 × 31)/(2 × 5) =
((3 × 5 × 11 × 31) ÷ 5) / ((2 × 5) ÷ 5) =
(3 × 11 × 31)/2 =
1,023/2
4. The fraction is an improper one, rewrite it as a mixed number (mixed fraction):
- A mixed number = an integer number and a proper fraction, of the same sign.
- Example 1: 2 1/5; Example 2: - 1 3/7.
- A proper fraction = the numerator is smaller than the denominator.
1,023 ÷ 2 = 511, remainder = 1 ⇒
1,023 = 511 × 2 + 1 ⇒
1,023/2 =
(511 × 2 + 1) / 2 =
(511 × 2) / 2 + 1/2 =
511 + 1/2 =
511 1/2